Rubber crawler traveling device

ABSTRACT

The present invention relates to a rubber track traveling device, which adjusts contact between a guide and a drive wheel to a normal state by adjusting the direction, meandering and the like of a rubber track particularly in relation to the drive wheel. The rubber track traveling device comprises: an idler wheel provided at a vehicle; a drive wheel; a wheel provided between the idler wheel and the drive wheel on a ground-contact surface side; and a rubber track entrained around the idler wheel, the drive wheel and the wheel, wherein an adjustment mechanism for orienting the direction of the rubber track to the direction of the vehicle is provided at the idler wheel and/or the wheel.

TECHNICAL FIELD

The present invention relates to a rubber track traveling device, and more particularly to a rubber track traveling device which ensures straight traveling.

BACKGROUND ART

A rubber track traveling device of the present invention will be described below in connection with a friction-drive type rubber track. Steel cords serving as tension reinforcing materials are embedded in a rubber elastic body, which has ends, in a longitudinal direction thereof. An endless rubber track is formed by overlapping the steel cords at the ends of the rubber elastic body. Guides are formed at predetermined intervals at a center of the rubber elastic body on an inner side thereof, while lugs are formed on an outer side of the rubber elastic body.

Even when rubber tracks look the same at the first glance, slight difference in the length in a transverse direction, presence of twists, or difference in the tension of the steel cords is inevitable.

For this reason, it has been suggested that, when each of the rubber tracks is mounted to a vehicle, the properties (characteristics) of the rubber track be understood first, and then the orientation of an idler wheel of the vehicle be adjusted in accordance with the properties of the rubber track.

FIG. 1 is a conceptual view of a rubber track traveling device. A rubber track 4 is entrained around an idler wheel 1, a drive wheel 2 and wheels 3. FIG. 2 is a view showing the state of the rubber track traveling device on a ground-contact surface. In FIG. 2, reference numeral 5 indicates guides formed at predetermined intervals on an inner peripheral surface of the rubber track 4 at a center thereof. Namely, the idler wheel 1, the drive wheel 2 and the wheels 3 travel at both sides of the guides 5. When the vehicle and the rubber track 4 do not travel in identical directions, the guides 5 collide with the respective wheels (1, 2 and 3). As a result, wear of the guides 5 increases, thereby decreasing the life of the rubber track 4.

Normally, an adjustment mechanism 6 may be provided at the idler wheels 1 in order to orient the direction of the rubber track 4 to the direction of the vehicle. Specifically, a mechanism which can adjust the orientation of the idler wheels 1 (in directions indicated by arrows) is provided in order to compensate for the characteristics of each rubber track.

However, in examining the causes of uneven wear of the guides 5 of the rubber track 4, it is found that the greatest effects occur when the guides 5 enter under the drive wheels 2, which are heavy and have a large diameter (i.e., the portion surrounded by a dotted line). Namely, even if the orientation of the rubber track 4 is adjusted at the idler wheels 1 as in the conventional art, this adjustment force does not last until it reaches the drive wheels 2 since the distance from the idler wheels 1 to the drive wheels 2 is long. As a result, the rubber track 4 proceeds in a different direction or meanders. Thus, uneven contact of the guides 5 with the drive wheels 2 at the portion surrounded by the dotted line is inevitable, and uneven wear of the guides 5 increases.

DISCLOSURE OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

In light of the above-described conventional technology, an object of the present invention is to adjust the direction, meandering and the like of the rubber track, particularly in relation to the drive wheels so that the contact between the guides and the drive wheels becomes normal.

MEANS FOR SOLVING THE PROBLEMS

In summary, the present invention provides a rubber track traveling device comprising: an idler wheel provided at a vehicle; a drive wheel; a wheel provided between the idler wheel and the drive wheel on a ground-contact surface side; and a rubber track entrained around the idler wheel, the drive wheel and the wheel, wherein an adjustment mechanism for orienting the direction of the rubber track to the direction of the vehicle is provided at the idler wheel and/or the wheel.

As for the wheel, the adjustment mechanism is preferably provided at the wheel closest to the drive wheel. Means for adjusting the orientation of shafts supporting the idler wheel and the wheel is a specific example of the adjustment mechanism.

EFFECTS OF THE INVENTION

The rubber track traveling device of the present invention has the above-described structure and preferably includes a plurality of adjustment mechanisms in order to orient the direction of the rubber track to the direction of the vehicle. With this structure, uneven wear of the guides is significantly reduced and, consequently, the life of the rubber track is greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual view of a conventional rubber track traveling device.

FIG. 2 is a view showing the state of the rubber track traveling device of FIG. 1 on a ground-contact surface.

FIG. 3 is a view showing the state of a rubber track traveling device of the present invention on a ground-contact surface.

FIG. 4 is a view showing a first embodiment of an adjustment mechanism.

FIG. 5 is a view showing a second embodiment of the adjustment mechanism.

FIG. 6 is a side view showing a third embodiment of the adjustment mechanism.

FIG. 7 is a plan view of FIG. 6.

FIG. 8 is a plan view showing a fourth embodiment of the adjustment mechanism.

BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, as described above, adjustment is preferably carried out at two portions. Particularly, when an adjustment function is provided at the wheel closest to the drive wheel, influence of the drive wheel on the guides can be minimized, and thus uneven wear of the guides can be prevented. Namely, even if adjustment is performed at the idler wheel, it is inevitable that the rubber track, which has passed the plurality of wheels, is slightly displaced from the original adjustment. Thus, the adjustment mechanism is normally provided at the wheels as well to correct the orientation of the rubber track, such that the rubber track is moved to the drive wheel with the best orientation possible. In this way, uneven wear of the guides can be significantly reduced.

Adjustment of the idler wheel and/or the wheel can be carried out in no other way than by trial and error because the adjustment varies according to the properties of the rubber track. Thus, the easiest process for adjustment is as follows. First, the rubber track is entrained around the respective wheels. Thereafter, the rubber track is made to travel straight several hundred meters. Then, the temperature of side surfaces of the guides of the rubber track is used to determine the friction thereof. Finally, based on the results, adjustment is sequentially carried out until an optimum value is obtained.

A specific embodiment of the adjustment mechanism is an adjustment mechanism including: a shaft supporting a pair of idler wheels and/or wheels; a connecting member connected to the shaft at a proximal end thereof; a shaft supporting the connecting member at a central portion thereof so that the connecting member is rotatable in a horizontal direction relative to the vehicle; a frame fixed to the vehicle and accommodating a distal end of the connecting member; and adjusting screws disposed at sides of the frame and being movable in the horizontal direction so as to be able to change the orientation of the distal end of the connecting member.

A second embodiment is an adjustment mechanism including: a shaft supporting a pair of idler wheels and/or wheels; a horizontal rod extending the shaft; a frame fixed to the vehicle and accommodating the horizontal rod; and adjusting screws disposed at sides of the frame and being movable in a horizontal direction so as to be able to change the orientation of the horizontal rod.

A third embodiment is an adjustment mechanism including: a shaft supporting a pair of idler wheels and/or wheels; a vertical rod connected to the shaft; a connecting member connected to the vertical rod; a frame fixed to the vehicle and accommodating the connecting member; and adjusting screws disposed at sides of the frame and being movable in a horizontal direction so as to be able to change the orientation of a distal end of the connecting member.

First Embodiment

The present invention will be described below in more detail with reference to the drawings. A conceptual view of the rubber track traveling device of the present invention is the same as FIG. 1. FIG. 3 is a view showing the state of the rubber track traveling device on a ground-contact surface. Reference numerals 1, 2, 3, 4, 5 and 6 in the drawings are defined as described above, and description thereof will be omitted.

An embodiment of the present invention is a structure in which the adjustment mechanism 6 (for adjustment in directions indicated by the arrows) is provided at the idler wheels 1 and at least wheels 30 closest to the drive wheels 2. Because of this structure, straight traveling and the like of the rubber track are adjusted twice, i.e., at the idler wheels 1 and the wheels 30. As a result, the rubber track contacts the drive wheels 2 with a desirable orientation, thereby significantly reducing (uneven) wear of the rubber track.

FIG. 4 is a view showing a first specific embodiment of the adjustment mechanism 6. The adjustment mechanism 6 which is provided at the idler wheels 1 will now be described. A connecting member 8 is provided at a shaft 7 supporting the idler wheels 1, and a proximal end 8 a of the connecting member 8 is connected to the shaft 7. Further, the connecting member 8 is supported by a shaft 91 at a central portion of the connecting member 8 so as to be rotatable in a horizontal direction. A distal end 8 b of the connecting member 8 is accommodated in a frame 101 fixed to a vehicle. Adjusting screws 111, 112 are provided at sides of the frame 101. The adjusting screws 111, 112 are adjusted so as to move and position the connecting member 8, whereby the orientation of the idler wheels 1 is adjusted.

More specifically, by adjusting the adjusting screws 111, 112 in direction A, the distal end 8 b of the connecting member 8 is oriented in the direction A and the proximal end 8 a is oriented in direction B. Thus, the shaft 7 connected to the proximal end 8 a is oriented in the direction B, and the idler wheels 1, 1 are also oriented in the direction B. This adjustment is repeated to achieve a desired orientation.

Second Embodiment

FIG. 5 is a view showing a second embodiment of the adjustment mechanism 6. In the second embodiment, the shaft 7 supporting the wheels 3 (30) is extended, and a horizontal portion (extended portion) 70 thereof is supported by a shaft 92 so as to be rotatable relative to a vehicle. The horizontal portion 70 is accommodated in a frame 102 as in the first embodiment. The adjusting screws 111, 112 are adjusted so as to change the orientation of the horizontal portion 70, whereby the orientation of the wheels 3 is adjusted. A specific process for adjustment is carried out as described in the previous paragraph. In this case, two pairs of the adjusting screws, i.e., the adjusting screws 111, 112 and adjusting screws 113, 114, are provided to enable fine adjustment of the orientation of a frame 12, which also enables fine adjustment of the orientation of the wheels 3, 3.

Third Embodiment

FIGS. 6 and 7 are views showing a third specific embodiment of the adjustment mechanism 6. In the third embodiment, a vertical shaft 93 is provided at the shaft 7 which supports the wheels 30 closest to the drive wheels 2. A connecting member (the frame 12 in this embodiment) is connected to the vertical shaft 93 and supported by a frame 13, which accommodates the frame 12 and is fixed to a vehicle, so as to be rotatable relative to the vehicle. The adjusting screws 111, 112, 113 and 114 are provided at sides of the frame 13 and adjusted so as to position the frame 12, whereby the orientation of the wheels 3 is adjusted. A specific process for adjustment is carried out as described in the previous paragraph. In this case, two pairs of the adjusting screws, i.e., the adjusting screws 111, 112 and the adjusting screws 113, 114, are provided to enable fine adjustment of the orientation of the frame 12, which also enables fine adjustment of the orientation of the wheels 3, 3.

Fourth Embodiment

FIG. 8 is a view showing another configuration of the third specific embodiment of the adjustment mechanism 6. The vertical shaft 93 is provided at the shaft 7 supporting, for example, wheels 31 which are the center pair of three pairs of wheels 3. The vertical shaft 93 is supported so as to be rotatable relative to a vehicle. Further, the frame 12 which is significantly long in the horizontal direction is fixed to the vertical shaft 93. The frame 13 fixed to the vehicle covers the frame 12. The adjusting screws 111, 112, 113 and 114 are provided at sides of the frame 13 in a transverse direction thereof. The adjusting screws 111, 112, 113 and 114 are adjusted so as to position the frame 12, whereby the orientation of the wheels 3 is adjusted. In this case, the elongated shape of the frame 13 in the transverse direction enables extremely fine adjustment with the adjusting screws. A specific process for adjustment is carried out as described in the previous paragraph. In this case, two pairs of the adjusting screws, i.e., the adjusting screws 111, 112 and the adjusting screws 113, 114, are provided to enable finer adjustment of the orientation of the frame 12, which also enables finer adjustment of the orientation of the wheels 3, 3.

Although the case in which the adjustment mechanism is provided at either the idler wheels 1 or the wheels 3 is described in the above embodiments, a similar adjustment mechanism can also be obtained by using this mechanism at both the idler wheels 1 and the wheels 3.

Industrial Applicability

The rubber track traveling device of the present invention preferably includes a plurality of adjustment mechanisms in order to orient the direction of the rubber track to the direction of the vehicle. With this structure, uneven wear of the guides is significantly reduced. Thus, the adjustment mechanism can be applied not only to low-speed rubber track traveling devices but also to rubber tracks for relatively high-speed vehicles such as off-road vehicles.

Description of the Reference Numerals

1: idler wheel

2: drive wheel

3, 30, 31: wheels

4: rubber track

5: guides

6: adjustment mechanism

7, 70: shafts supporting the idler wheel

8: connecting member

8 a: proximal end of the connecting member

8 b: distal end of the connecting member

91, 92, 93: shafts

101, 102, 12: frames

111, 112, 113, 114: adjusting screws

12: frame fixed to a vertical rod

13: frame fixed to a vehicle 

1] A rubber track traveling device comprising: an idler wheel provided at a vehicle; a drive wheel; a wheel provided between the idler wheel and the drive wheel on a ground-contact surface side; and a rubber track entrained around the idler wheel, the drive wheel and the wheel, wherein an adjustment mechanism for orienting the direction of the rubber track to the direction of the vehicle is provided at the idler wheel and/or the wheel. 2] The rubber track traveling device according to claim 1, wherein the adjustment mechanism is provided at the wheel closest to the drive wheel. 3] The rubber track traveling device according to claim 1, wherein the adjustment mechanism adjusts the orientation of a shaft supporting the idler wheel and/or the wheel. 4] The rubber track traveling device according to claim 1, wherein the adjustment mechanism includes: a shaft supporting a pair of idler wheels and/or wheels; a connecting member connected to the shaft at a proximal end thereof; a shaft supporting the connecting member at a central portion thereof so that the connecting member is rotatable in a horizontal direction relative to the vehicle; a frame fixed to the vehicle and accommodating a distal end of the connecting member; and adjusting screws disposed at sides of the frame and being movable in the horizontal direction so as to be able to change the orientation of the distal end of the connecting member. 5] The rubber track traveling device according to claim 1, wherein the adjustment mechanism includes: a shaft supporting a pair of idler wheels and/or wheels; a horizontal rod extending the shaft; a frame fixed to the vehicle and accommodating the horizontal rod; and adjusting screws disposed at sides of the frame and being movable in a horizontal direction so as to be able to change the orientation of the distal end of the horizontal rod. 6] The rubber track traveling device according to claim 1, wherein the adjustment mechanism includes: a shaft supporting a pair of idler wheels and/or wheels; a vertical rod connected to the shaft; a connecting member connected to the vertical rod; a frame fixed to the vehicle and accommodating the connecting member; and adjusting screws disposed at sides of the frame and being movable in a horizontal direction so as to be able to change the orientation of the distal end of the connecting member. 